Theoretical physicists James Hartle and Stephen Hawking, for example, proposed that rather than having a strict beginning as we would understand it, the universe evolved out of a "no-boundary" state ...

One such problem, along with dark matter and dark energy, is that the universe looks sort of flat. First, what do we mean by flat? "The density of the universe also determines its geometry.

A new "immersive visualization" will allow users to experience ... mathematics of relativity to actual consequences in the real universe," said Jeremy Schnittman, the NASA astrophysicist who ...